const std = @import("std");
const assert = std.debug.assert;
const json = std.json;
const Allocator = std.mem.Allocator;

// TODO: Maybe it would be good to move date time parsing to separate module
pub const parseDateTime = @import("./date_time/parse.zig").parseDateTime;

const json_utils = @import("json_utils.zig");
pub const Character = @import("character.zig");
const BoundedSlotsArray = @import("./slot_array.zig").BoundedSlotsArray;
const EnumStringUtils = @import("./enum_string_utils.zig").EnumStringUtils;
pub const Slot = @import("./slot.zig");
pub const Position = @import("./position.zig");

// Specification: https://api.artifactsmmo.com/docs

const Server = @This();

const log = std.log.scoped(.api);
pub const ItemId = u32;

allocator: Allocator,
client: std.http.Client,

server: []u8,
server_uri: std.Uri,

token: ?[]u8 = null,

item_codes: std.ArrayList([]u8),
characters: std.ArrayList(Character),

items: std.StringHashMap(Item),
maps: std.AutoHashMap(Position, MapTile),
resources: std.StringHashMap(Resource),
monsters: std.StringHashMap(Monster),

prefetched_resources: bool = false,
prefetched_maps: bool = false,
prefetched_monsters: bool = false,
prefetched_items: bool = false,

// ------------------------- API errors ------------------------

pub const APIError = error {
    ServerUnavailable,
    RequestFailed,
    ParseFailed,
    OutOfMemory
};

pub const MoveError = APIError || error {
    MapNotFound,
    CharacterIsBusy,
    CharacterAtDestination,
    CharacterNotFound,
    CharacterInCooldown
};

pub const FightError = APIError || error {
    CharacterIsBusy,
    CharacterIsFull,
    CharacterNotFound,
    CharacterInCooldown,
    MonsterNotFound,
};

pub const GatherError = APIError || error {
    CharacterIsBusy,
    NotEnoughSkill,
    CharacterIsFull,
    CharacterNotFound,
    CharacterInCooldown,
    ResourceNotFound
};

pub const BankDepositItemError = APIError || error {
    ItemNotFound,
    BankIsBusy,
    NotEnoughItems,
    CharacterIsBusy,
    CharacterNotFound,
    CharacterInCooldown,
    BankNotFound
};

pub const BankDepositGoldError = APIError || error {
    BankIsBusy,
    NotEnoughGold,
    CharacterIsBusy,
    CharacterNotFound,
    CharacterInCooldown,
    BankNotFound
};

pub const BankWithdrawGoldError = APIError || error {
    BankIsBusy,
    NotEnoughGold,
    CharacterIsBusy,
    CharacterNotFound,
    CharacterInCooldown,
    BankNotFound
};

pub const BankWithdrawItemError = APIError || error {
    ItemNotFound,
    BankIsBusy,
    NotEnoughItems,
    CharacterIsBusy,
    CharacterIsFull,
    CharacterNotFound,
    CharacterInCooldown,
    BankNotFound
};

pub const CraftError = APIError || error {
    RecipeNotFound,
    NotEnoughItems,
    CharacterIsBusy,
    NotEnoughSkill,
    CharacterIsFull,
    CharacterNotFound,
    CharacterInCooldown,
    WorkshopNotFound
};

pub const UnequipError = APIError || error {
    ItemNotFound, // TODO: Can this really occur? maybe a bug in docs
    CharacterIsBusy,
    SlotIsEmpty,
    CharacterIsFull,
    CharacterNotFound,
    CharacterInCooldown,
};

pub const EquipError = APIError || error {
    ItemNotFound,
    SlotIsFull,
    CharacterIsBusy,
    NotEnoughSkill,
    CharacterNotFound,
    CharacterInCooldown,
};

// ------------------------- API result structs ------------------------

pub const EquipmentSlot = @import("./equipment.zig").Slot;

pub const Skill = enum {
    weaponcrafting,
    gearcrafting,
    jewelrycrafting,
    cooking,
    woodcutting,
    mining,
};
pub const SkillUtils = EnumStringUtils(Skill, .{
    .{ "weaponcrafting" , Skill.weaponcrafting  },
    .{ "gearcrafting"   , Skill.gearcrafting    },
    .{ "jewelrycrafting", Skill.jewelrycrafting },
    .{ "cooking"        , Skill.cooking         },
    .{ "woodcutting"    , Skill.woodcutting     },
    .{ "mining"         , Skill.mining          },
});

const ServerStatus = struct {
    allocator: Allocator,
    status: []const u8,
    version: []const u8,
    characters_online: i64,

    pub fn parse(api: *Server, object: json.ObjectMap, allocator: Allocator) !ServerStatus {
        _ = api;

        return ServerStatus{
            .allocator = allocator,
            .characters_online = json_utils.getInteger(object, "characters_online") orelse return error.MissingProperty,
            .status = (try json_utils.dupeString(allocator, object, "status")) orelse return error.MissingStatus,
            .version = (try json_utils.dupeString(allocator, object, "version")) orelse return error.MissingVersion
        };
    }

    pub fn deinit(self: ServerStatus) void {
        self.allocator.free(self.status);
        self.allocator.free(self.version);
    }
};

pub const Cooldown = struct {
    pub const Reason = enum {
        movement,
        fight,
        crafting,
        gathering,
        buy_ge,
        sell_ge,
        delete_item,
        deposit_bank,
        withdraw_bank,
        equip,
        unequip,
        task,
        recycling,

        fn parse(str: []const u8) ?Reason {
            const Mapping = std.ComptimeStringMap(Reason, .{
                .{ "movement"     , .movement      },
                .{ "fight"        , .fight         },
                .{ "crafting"     , .crafting      },
                .{ "gathering"    , .gathering     },
                .{ "buy_ge"       , .buy_ge        },
                .{ "sell_ge"      , .sell_ge       },
                .{ "delete_item"  , .delete_item   },
                .{ "deposit_bank" , .deposit_bank  },
                .{ "withdraw_bank", .withdraw_bank },
                .{ "equip"        , .equip         },
                .{ "unequip"      , .unequip       },
                .{ "task"         , .task          },
                .{ "recycling"    , .recycling     },
            });

            return Mapping.get(str);
        }
    };

    expiration: f64,
    reason: Reason,

    pub fn parse(obj: json.ObjectMap) !Cooldown {
        const reason = try json_utils.getStringRequired(obj, "reason");
        const expiration = try json_utils.getStringRequired(obj, "expiration");

        return Cooldown{
            .expiration = parseDateTime(expiration) orelse return error.InvalidDateTime,
            .reason = Reason.parse(reason) orelse return error.UnknownReason
        };
    }
};

pub const FightResult = struct {
    const Details = struct {
        const Result = enum { win, lose };
        const Drops = BoundedSlotsArray(8);

        xp: i64,
        gold: i64,
        drops: Drops,
        result: Result,

        fn parse(api: *Server, obj: json.ObjectMap) !Details {
            const result = try json_utils.getStringRequired(obj, "result");
            var result_enum: Result = undefined;
            if (std.mem.eql(u8, result, "win")) {
                result_enum = .win;
            } else if (std.mem.eql(u8, result, "win")) {
                result_enum = .lose;
            } else {
                return error.InvalidProperty;
            }

            const drops_obj = json_utils.getArray(obj, "drops") orelse return error.MissingProperty;

            return Details{
                .xp = try json_utils.getIntegerRequired(obj, "xp"),
                .gold = try json_utils.getIntegerRequired(obj, "gold"),
                .drops = try Drops.parse(api, drops_obj),
                .result = result_enum,
            };
        }
    };

    cooldown: Cooldown,
    fight: Details,
    character: Character,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !FightResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;
        const fight = json_utils.getObject(obj, "fight") orelse return error.MissingProperty;
        const character = json_utils.getObject(obj, "character") orelse return error.MissingProperty;

        return FightResult{
            .cooldown = try Cooldown.parse(cooldown),
            .fight = try Details.parse(api, fight),
            .character = try Character.parse(api, character, allocator)
        };
    }

    pub fn parseError(status: std.http.Status) ?FightError {
        return switch (@intFromEnum(status)) {
            486 => FightError.CharacterIsBusy,
            497 => FightError.CharacterIsFull,
            498 => FightError.CharacterNotFound,
            499 => FightError.CharacterInCooldown,
            598 => FightError.MonsterNotFound,
            else => null
        };
    }
};

// TODO: Replace this with ItemSlot struct
pub const ItemIdQuantity = struct {
    id: ItemId,
    quantity: u64,

    pub fn init(id: ItemId, quantity: u64) ItemIdQuantity {
        return ItemIdQuantity{
            .id = id,
            .quantity = quantity
        };
    }

    pub fn parse(api: *Server, obj: json.ObjectMap) !ItemIdQuantity {
        const code = try json_utils.getStringRequired(obj, "code");
        const quantity = try json_utils.getIntegerRequired(obj, "quantity");
        if (quantity < 1) return error.InvalidQuantity;

        return ItemIdQuantity{
            .id = try api.getItemId(code),
            .quantity = @intCast(quantity)
        };
    }
};

pub const SkillResultDetails = struct {
    const Items = BoundedSlotsArray(8);

    xp: i64,
    items: Items,

    fn parse(api: *Server, obj: json.ObjectMap) !SkillResultDetails {
        const items = json_utils.getArray(obj, "items") orelse return error.MissingProperty;

        return SkillResultDetails{
            .xp = try json_utils.getIntegerRequired(obj, "xp"),
            .items = try Items.parse(api, items),
        };
    }
};

pub const GatherResult = struct {
    cooldown: Cooldown,
    details: SkillResultDetails,
    character: Character,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !GatherResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;
        const details = json_utils.getObject(obj, "details") orelse return error.MissingProperty;
        const character = json_utils.getObject(obj, "character") orelse return error.MissingProperty;

        return GatherResult{
            .cooldown = try Cooldown.parse(cooldown),
            .details = try SkillResultDetails.parse(api, details),
            .character = try Character.parse(api, character, allocator)
        };
    }

    pub fn parseError(status: std.http.Status) ?GatherError {
        return switch (@intFromEnum(status)) {
            486 => GatherError.CharacterIsBusy,
            493 => GatherError.NotEnoughSkill,
            497 => GatherError.CharacterIsFull,
            498 => GatherError.CharacterNotFound,
            499 => GatherError.CharacterInCooldown,
            598 => GatherError.ResourceNotFound,
            else => null
        };
    }
};

pub const MoveResult = struct {
    cooldown: Cooldown,
    character: Character,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !MoveResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;
        const character = json_utils.getObject(obj, "character") orelse return error.MissingProperty;

        return MoveResult{
            .cooldown = try Cooldown.parse(cooldown),
            .character = try Character.parse(api, character, allocator)
        };
    }

    pub fn parseError(status: std.http.Status) ?MoveError {
        return switch (@intFromEnum(status)) {
            404 => MoveError.MapNotFound,
            486 => MoveError.CharacterIsBusy,
            490 => MoveError.CharacterAtDestination,
            498 => MoveError.CharacterNotFound,
            499 => MoveError.CharacterInCooldown,
            else => null
        };
    }
};

pub const GoldTransactionResult = struct {
    cooldown: Cooldown,
    character: Character,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !GoldTransactionResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;
        const character = json_utils.getObject(obj, "character") orelse return error.MissingProperty;

        return GoldTransactionResult{
            .cooldown = try Cooldown.parse(cooldown),
            .character = try Character.parse(api, character, allocator)
        };
    }

    pub fn parseDepositError(status: std.http.Status) ?BankDepositGoldError {
        return switch (@intFromEnum(status)) {
            461 => BankDepositGoldError.BankIsBusy,
            486 => BankDepositGoldError.CharacterIsBusy,
            492 => BankDepositGoldError.NotEnoughGold,
            498 => BankDepositGoldError.CharacterNotFound,
            499 => BankDepositGoldError.CharacterInCooldown,
            598 => BankDepositGoldError.BankNotFound,
            else => null
        };
    }

    pub fn parseWithdrawError(status: std.http.Status) ?BankWithdrawGoldError {
        return switch (@intFromEnum(status)) {
            460 => BankWithdrawGoldError.NotEnoughGold,
            461 => BankWithdrawGoldError.BankIsBusy,
            486 => BankWithdrawGoldError.CharacterIsBusy,
            498 => BankWithdrawGoldError.CharacterNotFound,
            499 => BankWithdrawGoldError.CharacterInCooldown,
            598 => BankWithdrawGoldError.BankNotFound,
            else => null
        };
    }
};

pub const ItemTransactionResult = struct {
    cooldown: Cooldown,
    character: Character,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !ItemTransactionResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;
        const character = json_utils.getObject(obj, "character") orelse return error.MissingProperty;

        return ItemTransactionResult{
            .cooldown = try Cooldown.parse(cooldown),
            .character = try Character.parse(api, character, allocator)
        };
    }

    pub fn parseDepositError(status: std.http.Status) ?BankDepositItemError {
        return switch (@intFromEnum(status)) {
            404 => BankDepositItemError.ItemNotFound,
            461 => BankDepositItemError.BankIsBusy,
            478 => BankDepositItemError.NotEnoughItems,
            486 => BankDepositItemError.CharacterIsBusy,
            498 => BankDepositItemError.CharacterNotFound,
            499 => BankDepositItemError.CharacterInCooldown,
            598 => BankDepositItemError.BankNotFound,
            else => null
        };
    }

    pub fn parseWithdrawError(status: std.http.Status) ?BankWithdrawItemError {
        return switch (@intFromEnum(status)) {
            404 => BankWithdrawItemError.ItemNotFound,
            461 => BankWithdrawItemError.BankIsBusy,
            478 => BankWithdrawItemError.NotEnoughItems,
            486 => BankWithdrawItemError.CharacterIsBusy,
            497 => BankWithdrawItemError.CharacterIsFull,
            498 => BankWithdrawItemError.CharacterNotFound,
            499 => BankWithdrawItemError.CharacterInCooldown,
            598 => BankWithdrawItemError.BankNotFound,
            else => null
        };
    }
};

pub const CraftResult = struct {
    cooldown: Cooldown,
    details: SkillResultDetails,
    character: Character,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !CraftResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;
        const details = json_utils.getObject(obj, "details") orelse return error.MissingProperty;
        const character = json_utils.getObject(obj, "character") orelse return error.MissingProperty;

        return CraftResult{
            .cooldown = try Cooldown.parse(cooldown),
            .details = try SkillResultDetails.parse(api, details),
            .character = try Character.parse(api, character, allocator)
        };
    }

    pub fn parseError(status: std.http.Status) ?CraftError {
        return switch (@intFromEnum(status)) {
            404 => CraftError.RecipeNotFound,
            478 => CraftError.NotEnoughItems,
            486 => CraftError.CharacterIsBusy,
            493 => CraftError.NotEnoughSkill,
            497 => CraftError.CharacterIsFull,
            498 => CraftError.CharacterNotFound,
            499 => CraftError.CharacterInCooldown,
            598 => CraftError.WorkshopNotFound,
            else => null
        };
    }
};

pub const UnequipResult = struct {
    cooldown: Cooldown,
    item: ItemId,

    pub fn parse(api: *Server, obj: json.ObjectMap) !UnequipResult {
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;

        const item = json_utils.getObject(obj, "item") orelse return error.MissingProperty;
        const item_code = json_utils.getString(item, "code") orelse return error.MissingProperty;

        const item_id = try api.getItemId(item_code);

        // TODO: Might as well save information about time, because full details about it are given

        return UnequipResult{
            .cooldown = try Cooldown.parse(cooldown),
            .item = item_id
        };
    }

    pub fn parseError(status: std.http.Status) ?UnequipError {
        return switch (@intFromEnum(status)) {
            404 => UnequipError.ItemNotFound,
            486 => UnequipError.CharacterIsBusy,
            491 => UnequipError.SlotIsEmpty,
            497 => UnequipError.CharacterIsFull,
            498 => UnequipError.CharacterNotFound,
            499 => UnequipError.CharacterInCooldown,
            else => null
        };
    }
};

pub const EquipResult = struct {
    cooldown: Cooldown,

    pub fn parse(api: *Server, obj: json.ObjectMap) !EquipResult {
        _ = api;
        const cooldown = json_utils.getObject(obj, "cooldown") orelse return error.MissingProperty;

        // TODO: Might as well save information about time, because full details about it are given

        return EquipResult{
            .cooldown = try Cooldown.parse(cooldown)
        };
    }

    pub fn parseError(status: std.http.Status) ?EquipError {
        return switch (@intFromEnum(status)) {
            404 => EquipError.ItemNotFound,
            478 => EquipError.ItemNotFound, // TODO: What is the difference between 404 and 478?
            485 => EquipError.SlotIsFull,
            486 => EquipError.CharacterIsBusy,
            491 => EquipError.SlotIsFull, // TODO: What is the difference between 485 and 491?
            496 => EquipError.NotEnoughSkill,
            498 => EquipError.CharacterNotFound,
            499 => EquipError.CharacterInCooldown,
            else => null
        };
    }
};

pub const MapContentType = enum {
    monster,
    resource,
    workshop,
    bank,
    grand_exchange,
    tasks_master,
};
pub const MapContentTypeUtils = EnumStringUtils(MapContentType, .{
    .{ "monster"       , .monster        },
    .{ "resource"      , .resource       },
    .{ "workshop"      , .workshop       },
    .{ "bank"          , .bank           },
    .{ "grand_exchange", .grand_exchange },
    .{ "tasks_master"  , .tasks_master   },
});

pub const MapTile = struct {
    pub const MapContent = struct {
        type: MapContentType,
        code: []u8,
    };

    name: []u8,
    skin: []u8,
    position: Position,
    content: ?MapContent,

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !MapTile {
        _ = api;

        var content: ?MapContent = null;
        if (json_utils.getObject(obj, "content")) |content_obj| {
            const content_type = json_utils.getString(content_obj, "type") orelse return error.MissingProperty;

            content = MapContent{
                .type = MapContentTypeUtils.fromString(content_type) orelse return error.InvalidContentType,
                .code = (try json_utils.dupeString(allocator, content_obj, "code")) orelse return error.MissingProperty,
            };
        }

        const x = json_utils.getInteger(obj, "x") orelse return error.MissingProperty;
        const y = json_utils.getInteger(obj, "y") orelse return error.MissingProperty;

        return MapTile{
            .name = (try json_utils.dupeString(allocator, obj, "name")) orelse return error.MissingProperty,
            .skin = (try json_utils.dupeString(allocator, obj, "skin")) orelse return error.MissingProperty,
            .position = Position.init(x, y),
            .content = content
        };
    }

    pub fn deinit(self: MapTile, allocator: Allocator) void {
        allocator.free(self.name);
        allocator.free(self.skin);
        if (self.content) |content| {
            allocator.free(content.code);
        }
    }
};

pub const ItemType = enum {
    consumable,
    body_armor,
    weapon,
    resource,
    leg_armor,
    helmet,
    boots,
    shield,
    amulet,
    ring,
    artifact,
    currency,
};
const ItemTypeUtils = EnumStringUtils(ItemType, .{
    .{ "consumable",  .consumable },
    .{ "body_armor",  .body_armor },
    .{ "weapon"    ,  .weapon     },
    .{ "resource"  ,  .resource   },
    .{ "leg_armor" ,  .leg_armor  },
    .{ "helmet"    ,  .helmet     },
    .{ "boots"     ,  .boots      },
    .{ "shield"    ,  .shield     },
    .{ "amulet"    ,  .amulet     },
    .{ "ring"      ,  .ring       },
    .{ "artifact"  ,  .artifact   },
    .{ "currency"  ,  .currency   },
});

pub const Item = struct {
    pub const Recipe = struct {
        const Items = BoundedSlotsArray(8);

        skill: Skill,
        level: u64,
        quantity: u64,
        items: Items,

        pub fn parse(api: *Server, obj: json.ObjectMap) !Recipe {
            const skill = json_utils.getString(obj, "skill") orelse return error.MissingProperty;
            const level = json_utils.getInteger(obj, "level") orelse return error.MissingProperty;
            if (level < 1) return error.InvalidLevel;

            const quantity = json_utils.getInteger(obj, "quantity") orelse return error.MissingProperty;
            if (quantity < 1) return error.InvalidQuantity;

            const items = json_utils.getArray(obj, "items") orelse return error.MissingProperty;

            return Recipe{
                .skill = SkillUtils.fromString(skill) orelse return error.InvalidSkill,
                .level = @intCast(level),
                .quantity = @intCast(quantity),
                .items = try Items.parse(api, items)
            };
        }
    };

    allocator: Allocator,
    name: []u8,
    code: []u8,
    level: u64,
    type: ItemType,
    subtype: []u8,
    description: []u8,
    craft: ?Recipe,
    // TODO: effects

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !Item {
        const level = json_utils.getInteger(obj, "level") orelse return error.MissingProperty;
        if (level < 1) return error.InvalidLevel;

        const craft = json_utils.getObject(obj, "craft");
        const item_type_str = try json_utils.getStringRequired(obj, "type");

        return Item{
            .allocator = allocator,
            .name = (try json_utils.dupeString(allocator, obj, "name")) orelse return error.MissingProperty,
            .code = (try json_utils.dupeString(allocator, obj, "code")) orelse return error.MissingProperty,
            .level = @intCast(level),
            .type = ItemTypeUtils.fromString(item_type_str) orelse return error.InvalidType,
            .subtype = (try json_utils.dupeString(allocator, obj, "subtype")) orelse return error.MissingProperty,
            .description = (try json_utils.dupeString(allocator, obj, "description")) orelse return error.MissingProperty,
            .craft = if (craft != null) try Recipe.parse(api, craft.?) else null
        };
    }

    pub fn deinit(self: Item) void {
        self.allocator.free(self.name);
        self.allocator.free(self.code);
        self.allocator.free(self.subtype);
        self.allocator.free(self.description);
    }
};

pub const ItemWithGE = struct {
    item: Item,
    // TODO: Grand exchange

    pub fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !ItemWithGE {
        const item_obj = json_utils.getObject(obj, "item") orelse return error.MissingProperty;
        const ge_obj   = json_utils.getObject(obj, "ge") orelse return error.MissingProperty;
        _ = ge_obj;

        return ItemWithGE{
            .item = try Item.parse(api, item_obj, allocator),
        };
    }
};

pub const ResourceSkill = enum {
    mining,
    woodcutting,
    fishing,
};
const ResourceSkillUtils = EnumStringUtils(ResourceSkill, .{
    .{ "mining"     , .mining      },
    .{ "woodcutting", .woodcutting },
    .{ "fishing"    , .fishing     },
});

const DropRates = std.BoundedArray(DropRate, 8);
const DropRate = struct {
    item_id: ItemId,
    rate: u64,
    min_quantity: u64,
    max_quantity: u64,

    fn parse(api: *Server, obj: json.ObjectMap) !DropRate {
        const rate = try json_utils.getIntegerRequired(obj, "rate");
        if (rate < 1) {
            return error.InvalidRate;
        }

        const min_quantity = try json_utils.getIntegerRequired(obj, "min_quantity");
        if (min_quantity < 1) {
            return error.InvalidMinQuantity;
        }

        const max_quantity = try json_utils.getIntegerRequired(obj, "max_quantity");
        if (max_quantity < 1) {
            return error.InvalidMinQuantity;
        }

        const code_str = try json_utils.getStringRequired(obj, "code");
        const item_id = try api.getItemId(code_str);

        return DropRate{
            .item_id = item_id,
            .rate = @intCast(rate),
            .min_quantity = @intCast(min_quantity),
            .max_quantity = @intCast(max_quantity)
        };
    }

    fn parseList(api: *Server, array: json.Array) !DropRates {
        var drops = DropRates.init(0) catch unreachable;
        for (array.items) |drop_value| {
            const drop_obj = json_utils.asObject(drop_value) orelse return error.InvalidObject;
            try drops.append(try DropRate.parse(api, drop_obj));
        }
        return drops;
    }

    fn doesListContain(drops: *DropRates, item_id: ItemId) bool {
        for (drops.constSlice()) |drop| {
            if (drop.item_id == item_id) {
                return true;
            }
        }
        return false;
    }
};

pub const Resource = struct {
    name: []u8,
    code: []u8,
    skill: ResourceSkill,
    level: u64,
    drops: DropRates,

    fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !Resource {
        const drops_array = json_utils.getArray(obj, "drops") orelse return error.MissingProperty;

        const level = try json_utils.getIntegerRequired(obj, "level");
        if (level < 0) {
            return error.InvalidLevel;
        }

        const skill_str = try json_utils.getStringRequired(obj, "skill");

        return Resource{
            .name = try json_utils.dupeStringRequired(allocator, obj, "name"),
            .code = try json_utils.dupeStringRequired(allocator, obj, "code"),
            .level = @intCast(level),
            .skill = ResourceSkillUtils.fromString(skill_str) orelse return error.InvalidSkill,
            .drops = try DropRate.parseList(api, drops_array)
        };
    }

    fn deinit(self: Resource, allocator: Allocator) void {
        allocator.free(self.name);
        allocator.free(self.code);
    }
};

pub const Monster = struct {
    const ElementalStats = struct {
        attack: i64,
        resistance: i64,

        pub fn parse(object: json.ObjectMap, attack: []const u8, resistance: []const u8) !ElementalStats {
            return ElementalStats{
                .attack = try json_utils.getIntegerRequired(object, attack),
                .resistance = try json_utils.getIntegerRequired(object, resistance),
            };
        }
    };

    name: []u8,
    code: []u8,
    level: u64,
    hp: u64,
    min_gold: u64,
    max_gold: u64,

    fire: ElementalStats,
    earth: ElementalStats,
    water: ElementalStats,
    air: ElementalStats,

    drops: DropRates,

    fn parse(api: *Server, obj: json.ObjectMap, allocator: Allocator) !Monster {
        const drops_array = json_utils.getArray(obj, "drops") orelse return error.MissingProperty;

        const min_gold = try json_utils.getIntegerRequired(obj, "min_gold");
        if (min_gold < 0) {
            return error.InvalidMinGold;
        }

        const max_gold = try json_utils.getIntegerRequired(obj, "max_gold");
        if (max_gold < 0) {
            return error.InvalidMaxGold;
        }

        const level = try json_utils.getIntegerRequired(obj, "level");
        if (level < 0) {
            return error.InvalidLevel;
        }

        const hp = try json_utils.getIntegerRequired(obj, "hp");
        if (hp < 0) {
            return error.InvalidHp;
        }

        return Monster{
            .name = try json_utils.dupeStringRequired(allocator, obj, "name"),
            .code = try json_utils.dupeStringRequired(allocator, obj, "code"),
            .level = @intCast(level),
            .hp    = @intCast(hp),

            .fire  = try ElementalStats.parse(obj, "attack_fire" , "res_fire" ),
            .earth = try ElementalStats.parse(obj, "attack_earth", "res_earth"),
            .water = try ElementalStats.parse(obj, "attack_water", "res_water"),
            .air   = try ElementalStats.parse(obj, "attack_air"  , "res_air"  ),

            .min_gold = @intCast(min_gold),
            .max_gold = @intCast(max_gold),
            .drops = try DropRate.parseList(api, drops_array)
        };
    }

    fn deinit(self: Monster, allocator: Allocator) void {
        allocator.free(self.name);
        allocator.free(self.code);
    }
};

pub const ArtifactsFetchResult = struct {
    arena: std.heap.ArenaAllocator,
    status: std.http.Status,
    body: ?json.Value = null,

    fn deinit(self: ArtifactsFetchResult) void {
        self.arena.deinit();
    }
};

fn appendQueryParam(query: *std.ArrayList(u8), key: []const u8, value: []const u8) !void {
    if (query.items.len > 0) {
        try query.appendSlice("&");
    }

    try query.appendSlice(key);
    try query.appendSlice("=");
    try query.appendSlice(value);
}

// ------------------------- General API methods ------------------------

pub fn init(allocator: Allocator) !Server {
    const url = try allocator.dupe(u8, "https://api.artifactsmmo.com");
    const uri = std.Uri.parse(url) catch unreachable;

    return Server{
        .allocator = allocator,
        .client = .{ .allocator = allocator },
        .server = url,
        .server_uri = uri,

        .item_codes = std.ArrayList([]u8).init(allocator),
        .characters = std.ArrayList(Character).init(allocator),
        .items = std.StringHashMap(Item).init(allocator),
        .maps = std.AutoHashMap(Position, MapTile).init(allocator),
        .resources = std.StringHashMap(Resource).init(allocator),
        .monsters = std.StringHashMap(Monster).init(allocator),
    };
}

pub fn deinit(self: *Server) void {
    self.client.deinit();
    self.allocator.free(self.server);
    if (self.token) |str| self.allocator.free(str);

    for (self.item_codes.items) |code| {
        self.allocator.free(code);
    }
    self.item_codes.deinit();

    for (self.characters.items) |*char| {
        char.deinit();
    }
    self.characters.deinit();

    var itemsIter = self.items.valueIterator();
    while (itemsIter.next()) |item| {
        item.deinit();
    }
    self.items.deinit();

    var mapsIter = self.maps.valueIterator();
    while (mapsIter.next()) |map| {
        map.deinit(self.allocator);
    }
    self.maps.deinit();

    var resourcesIter = self.resources.valueIterator();
    while (resourcesIter.next()) |resource| {
        resource.deinit(self.allocator);
    }
    self.resources.deinit();

    var monstersIter = self.monsters.valueIterator();
    while (monstersIter.next()) |monster| {
        monster.deinit(self.allocator);
    }
    self.monsters.deinit();
}

const FetchOptions = struct {
    method: std.http.Method,
    path: []const u8,
    payload: ?[]const u8 = null,

    query: ?[]const u8 = null,

    page: ?u64 = null,
    page_size: ?u64 = null,
    paginated: bool = false
};

fn allocPaginationParams(allocator: Allocator, page: u64, page_size: ?u64) ![]u8 {
    if (page_size) |size| {
        return try std.fmt.allocPrint(allocator, "page={}&size={}", .{page, size});
    } else {
        return try std.fmt.allocPrint(allocator, "page={}", .{page});
    }
}

// TODO: add retries when hitting a ratelimit
fn fetch(self: *Server, options: FetchOptions) APIError!ArtifactsFetchResult {
    const method = options.method;
    const path = options.path;
    const payload = options.payload;

    var uri = self.server_uri;
    uri.path = .{ .raw = path };

    var arena = std.heap.ArenaAllocator.init(self.allocator);
    errdefer arena.deinit();

    var result_status: std.http.Status = .ok;
    var result_body: ?json.Value = null;

    var current_page: u64 = options.page orelse 1;
    var total_pages: u64 = 1;
    var fetch_results = std.ArrayList(json.Value).init(arena.allocator());

    const has_query = options.query != null and options.query.?.len > 0;

    while (true) : (current_page += 1) {
        var pagination_params: ?[]u8 = null;
        defer if (pagination_params) |str| self.allocator.free(str);

        if (options.paginated) {
            pagination_params = try allocPaginationParams(self.allocator, current_page, options.page_size);
        }

        if (has_query and pagination_params != null) {
            const combined = try std.mem.join(self.allocator, "&", &.{ options.query.?, pagination_params.? });
            self.allocator.free(pagination_params.?);
            pagination_params = combined;

            uri.query = .{ .raw = combined };
        } else if (pagination_params != null) {
            uri.query = .{ .raw = pagination_params.? };
        } else if (has_query) {
            uri.query = .{ .raw = options.query.? };
        }

        var response_storage = std.ArrayList(u8).init(arena.allocator());
        var opts = std.http.Client.FetchOptions{
            .method = method,
            .location = .{ .uri = uri },
            .payload = payload,
            .response_storage = .{ .dynamic = &response_storage },
        };

        var authorization_header: ?[]u8 = null;
        defer if (authorization_header) |str| self.allocator.free(str);

        if (self.token) |token| {
            authorization_header = std.fmt.allocPrint(self.allocator, "Bearer {s}", .{token}) catch return APIError.OutOfMemory;
            opts.headers.authorization = .{ .override = authorization_header.? };
        }

        if (uri.query) |query| {
            log.debug("fetch {} {s}?{s}", .{method, path, query.raw});
        } else {
            log.debug("fetch {} {s}", .{method, path});
        }

        const result = self.client.fetch(opts) catch return APIError.RequestFailed;
        const response_body = response_storage.items;

        log.debug("fetch result {}", .{result.status});

        if (result.status == .service_unavailable) {
            return APIError.ServerUnavailable;
        } else if (result.status != .ok) {
            return ArtifactsFetchResult{
                .arena = arena,
                .status = result.status
            };
        }

        const parsed = json.parseFromSliceLeaky(json.Value, arena.allocator(), response_body, .{ .allocate = .alloc_if_needed }) catch return APIError.ParseFailed;
        if (parsed != json.Value.object) {
            return APIError.ParseFailed;
        }

        result_status = result.status;

        if (options.paginated) {
            const total_pages_i64 = json_utils.getInteger(parsed.object, "pages") orelse return APIError.ParseFailed;
            if (total_pages_i64 < 0) return APIError.ParseFailed;
            total_pages = @intCast(total_pages_i64);

            const page_results = json_utils.getArray(parsed.object, "data") orelse return APIError.ParseFailed;
            fetch_results.appendSlice(page_results.items) catch return APIError.OutOfMemory;

            if (current_page >= total_pages) break;
        } else {
            result_body = parsed.object.get("data");
            break;
        }
    }

    if (options.paginated) {
        result_body = json.Value{ .array = fetch_results };
    }

    return ArtifactsFetchResult{
        .status = result_status,
        .arena = arena,
        .body = result_body
    };
}

fn handleFetchError(
    status: std.http.Status,
    Error: type,
    parseError: ?fn (status: std.http.Status) ?Error,
) ?Error {
    if (status != .ok) {
        if (Error != APIError) {
            if (parseError == null) {
                @compileError("`parseError` must be defined, if `Error` is not `APIError`");
            }

            if (parseError.?(status)) |error_value| {
                return error_value;
            }
        } else {
            if (parseError != null) {
                @compileError("`parseError` must be null");
            }
        }
    }

    return null;
}

fn fetchOptionalObject(
    self: *Server,
    Error: type,
    parseError: ?fn (status: std.http.Status) ?Error,
    Object: type,
    parseObject: anytype,
    parseObjectArgs: anytype,
    fetchOptions: FetchOptions,
) Error!?Object {
    if (@typeInfo(@TypeOf(parseObject)) != .Fn) {
        @compileError("`parseObject` must be a function");
    }

    const result = try self.fetch(fetchOptions);
    defer result.deinit();

    if (handleFetchError(result.status, Error, parseError)) |error_value| {
        return error_value;
    }
    if (result.status == .not_found) {
        return null;
    }
    if (result.status != .ok) {
        return APIError.RequestFailed;
    }

    if (result.body == null) {
        return APIError.ParseFailed;
    }

    const body = json_utils.asObject(result.body.?) orelse return APIError.ParseFailed;
    return @call(.auto, parseObject, .{ self, body } ++ parseObjectArgs) catch return APIError.ParseFailed;
}

fn fetchObject(
    self: *Server,
    Error: type,
    parseError: ?fn (status: std.http.Status) ?Error,
    Object: type,
    parseObject: anytype,
    parseObjectArgs: anytype,
    fetchOptions: FetchOptions
) Error!Object {
    const result = try self.fetchOptionalObject(Error, parseError, Object, parseObject, parseObjectArgs, fetchOptions);
    return result orelse return APIError.RequestFailed;
}

fn fetchOptionalArray(
    self: *Server,
    allocator: Allocator,
    Error: type,
    parseError: ?fn (status: std.http.Status) ?Error,
    Object: type,
    parseObject: anytype,
    parseObjectArgs: anytype,
    fetchOptions: FetchOptions
) Error!?std.ArrayList(Object) {
    if (@typeInfo(@TypeOf(parseObject)) != .Fn) {
        @compileError("`parseObject` must be a function");
    }

    const result = try self.fetch(fetchOptions);
    defer result.deinit();

    if (handleFetchError(result.status, Error, parseError)) |error_value| {
        return error_value;
    }
    if (result.status == .not_found) {
        return null;
    }
    if (result.status != .ok) {
        return APIError.RequestFailed;
    }

    if (result.body == null) {
        return APIError.ParseFailed;
    }

    var array = std.ArrayList(Object).init(allocator);
    errdefer {
        if (std.meta.hasFn(Object, "deinit")) {
            for (array.items) |*item| {
                _ = item;
                // TODO:
                // item.deinit();
            }
        }
        array.deinit();
    }

    const result_data = json_utils.asArray(result.body.?) orelse return APIError.ParseFailed;
    for (result_data.items) |result_item| {
        const item_obj = json_utils.asObject(result_item) orelse return APIError.ParseFailed;

        const parsed_item = @call(.auto, parseObject, .{ self, item_obj } ++ parseObjectArgs) catch return APIError.ParseFailed;
        array.append(parsed_item) catch return APIError.OutOfMemory;
    }

    return array;
}

fn fetchArray(
    self: *Server,
    allocator: Allocator,
    Error: type,
    parseError: ?fn (status: std.http.Status) ?Error,
    Object: type,
    parseObject: anytype,
    parseObjectArgs: anytype,
    fetchOptions: FetchOptions
) Error!std.ArrayList(Object) {
    const result = try self.fetchOptionalArray(allocator, Error, parseError, Object, parseObject, parseObjectArgs, fetchOptions);
    return result orelse return APIError.RequestFailed;
}

pub fn setURL(self: *Server, url: []const u8) !void {
    const url_dupe = self.allocator.dupe(u8, url);
    errdefer self.allocator.free(url_dupe);

    const uri = try std.Uri.parse(url_dupe);

    self.allocator.free(self.server);
    self.server = url_dupe;
    self.server_uri = uri;
}

pub fn setToken(self: *Server, token: ?[]const u8) !void {
    var new_token: ?[]u8 = null;
    if (token != null) {
        new_token = try self.allocator.dupe(u8, token.?);
    }

    if (self.token) |str| self.allocator.free(str);
    self.token = new_token;
}

pub fn getItemId(self: *Server, code: []const u8) !ItemId {
    assert(code.len != 0);

    for (0.., self.item_codes.items) |i, item_code| {
        if (std.mem.eql(u8, code, item_code)) {
            return @intCast(i);
        }
    }

    const code_dupe = try self.allocator.dupe(u8, code);
    errdefer self.allocator.free(code_dupe);
    try self.item_codes.append(code_dupe);

    return @intCast(self.item_codes.items.len - 1);
}

pub fn getItemCode(self: *const Server, id: ItemId) ?[]const u8 {
    if (id >= self.item_codes.items.len) {
        return null;
    }

    return self.item_codes.items[id];
}

pub fn getItemIdJson(self: *Server, object: json.ObjectMap, name: []const u8) !?ItemId {
    const code = try json_utils.getStringRequired(object, name);
    if (code.len == 0) {
        return null;
    }

    return try self.getItemId(code);
}

fn findCharacterIndex(self: *const Server, name: []const u8) ?usize {
    for (0.., self.characters.items) |i, character| {
        if (std.mem.eql(u8, character.name, name)) {
            return i;
        }
    }

    return null;
}

fn addOrUpdateCharacter(self: *Server, character: Character) !void {
    if (self.findCharacterIndex(character.name)) |found| {
        self.characters.items[found].deinit();
        self.characters.items[found] = character;
    } else {
        try self.characters.append(character);
    }
}

pub fn findCharacter(self: *const Server, name: []const u8) ?Character {
    if (self.findCharacterIndex(name)) |index| {
        return self.characters.items[index];
    }

    return null;
}

pub fn findCharacterPtr(self: *Server, name: []const u8) ?*Character {
    if (self.findCharacterIndex(name)) |index| {
        return &self.characters.items[index];
    }

    return null;
}

// TODO: Remove this function
pub fn findItem(self: *const Server, name: []const u8) ?Item {
    return self.items.get(name);
}

// TODO: Remove this function
pub fn findMap(self: *const Server, position: Position) ?MapTile {
    return self.maps.get(position);
}

fn addOrUpdateItem(self: *Server, item: Item) !void {
    var entry = try self.items.getOrPut(item.code);
    if (entry.found_existing) {
        entry.value_ptr.deinit();
    }
    entry.value_ptr.* = item;
}

fn addOrUpdateMap(self: *Server, map: MapTile) !void {
    var entry = try self.maps.getOrPut(map.position);
    if (entry.found_existing) {
        entry.value_ptr.deinit(self.allocator);
    }
    entry.value_ptr.* = map;
}

fn addOrUpdateResource(self: *Server, resource: Resource) !void {
    var entry = try self.resources.getOrPut(resource.code);
    if (entry.found_existing) {
        entry.value_ptr.deinit(self.allocator);
    }
    entry.value_ptr.* = resource;
}

fn addOrUpdateMonster(self: *Server, monster: Monster) !void {
    var entry = try self.monsters.getOrPut(monster.code);
    if (entry.found_existing) {
        entry.value_ptr.deinit(self.allocator);
    }
    entry.value_ptr.* = monster;
}

pub fn prefetch(self: *Server) !void {
    self.prefetched_resources = false;
    self.prefetched_maps = false;
    self.prefetched_monsters = false;
    self.prefetched_items = false;

    try self.prefetchResources();
    try self.prefetchMaps();
    try self.prefetchMonsters();
    try self.prefetchItems();
}

pub fn prefetchResources(self: *Server) !void {
    var resources = try self.getResources(.{});
    defer resources.deinit();

    self.prefetched_resources = true;
}

pub fn prefetchMaps(self: *Server) !void {
    var maps = try self.getMaps(.{});
    defer maps.deinit();

    self.prefetched_maps = true;
}

pub fn prefetchMonsters(self: *Server) !void {
    var monsters = try self.getMonsters(.{});
    defer monsters.deinit();

    self.prefetched_monsters = true;
}

pub fn prefetchItems(self: *Server) !void {
    var items = try self.getItems(.{});
    defer items.deinit();

    self.prefetched_items = true;
}

// ------------------------- Endpoints ------------------------

pub fn getServerStatus(self: *Server) !ServerStatus {
    return try self.fetchObject(
        APIError,
        null,
        ServerStatus,
        ServerStatus.parse, .{ self.allocator },
        .{ .method = .GET, .path = "/" }
    );
}

pub fn getCharacter(self: *Server, name: []const u8) APIError!?Character {
    const path = try std.fmt.allocPrint(self.allocator, "/characters/{s}", .{name});
    defer self.allocator.free(path);

    var maybe_character = try self.fetchOptionalObject(
        APIError,
        null,
        Character,
        Character.parse, .{ self.allocator },
        .{ .method = .GET, .path = path }
    );

    if (maybe_character) |*character| {
        errdefer character.deinit();
        try self.addOrUpdateCharacter(character.*);
        return character.*;
    } else {
        return null;
    }
}

pub fn listMyCharacters(self: *Server) APIError!std.ArrayList(Character) {
    const characters = try self.fetchArray(
        self.allocator,
        APIError,
        null,
        Character,
        Character.parse, .{ self.allocator },
        .{ .method = .GET, .path = "/my/characters" }
    );
    errdefer characters.deinit();
    for (characters.items) |character| {
        try self.addOrUpdateCharacter(character);
    }

    return characters;
}

pub fn actionFight(self: *Server, name: []const u8) FightError!FightResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/fight", .{name});
    defer self.allocator.free(path);

    const result = try self.fetchObject(
        FightError,
        FightResult.parseError,
        FightResult,
        FightResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionGather(self: *Server, name: []const u8) GatherError!GatherResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/gathering", .{name});
    defer self.allocator.free(path);

    const result = try self.fetchObject(
        GatherError,
        GatherResult.parseError,
        GatherResult,
        GatherResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionMove(self: *Server, name: []const u8, x: i64, y: i64) MoveError!MoveResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/move", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"x\":{},\"y\":{} }}", .{x, y});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        MoveError,
        MoveResult.parseError,
        MoveResult,
        MoveResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionBankDepositGold(
    self: *Server,
    name: []const u8,
    quantity: u64
) BankDepositGoldError!GoldTransactionResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/bank/deposit/gold", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"quantity\":{} }}", .{quantity});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        BankDepositGoldError,
        GoldTransactionResult.parseDepositError,
        GoldTransactionResult,
        GoldTransactionResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionBankDepositItem(
    self: *Server,
    name: []const u8,
    code: []const u8,
    quantity: u64
) BankDepositItemError!ItemTransactionResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/bank/deposit", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"code\":\"{s}\",\"quantity\":{} }}", .{code, quantity});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        BankDepositItemError,
        ItemTransactionResult.parseDepositError,
        ItemTransactionResult,
        ItemTransactionResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionBankWithdrawGold(
    self: *Server,
    name: []const u8,
    quantity: u64
) BankDepositGoldError!GoldTransactionResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/bank/withdraw/gold", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"quantity\":{} }}", .{quantity});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        BankWithdrawGoldError,
        GoldTransactionResult.parseWithdrawError,
        GoldTransactionResult,
        GoldTransactionResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionBankWithdrawItem(
    self: *Server,
    name: []const u8,
    code: []const u8,
    quantity: u64
) BankWithdrawItemError!ItemTransactionResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/bank/withdraw", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"code\":\"{s}\",\"quantity\":{} }}", .{code, quantity});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        BankWithdrawItemError,
        ItemTransactionResult.parseWithdrawError,
        ItemTransactionResult,
        ItemTransactionResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionCraft(
    self: *Server,
    name: []const u8,
    code: []const u8,
    quantity: u64
) !CraftResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/crafting", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"code\":\"{s}\",\"quantity\":{} }}", .{code, quantity});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        CraftError,
        CraftResult.parseError,
        CraftResult,
        CraftResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionUnequip(
    self: *Server,
    name: []const u8,
    slot: EquipmentSlot
) UnequipError!UnequipResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/unequip", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"slot\":\"{s}\" }}", .{slot.name()});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        UnequipError,
        UnequipResult.parseError,
        UnequipResult,
        UnequipResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn actionEquip(
    self: *Server,
    name: []const u8,
    slot: EquipmentSlot,
    code: []const u8
) EquipError!EquipResult {
    const path = try std.fmt.allocPrint(self.allocator, "/my/{s}/action/equip", .{name});
    defer self.allocator.free(path);

    const payload = try std.fmt.allocPrint(self.allocator, "{{ \"slot\":\"{s}\",\"code\":\"{s}\" }}", .{slot.name(), code});
    defer self.allocator.free(payload);

    const result = try self.fetchObject(
        EquipError,
        EquipResult.parseError,
        EquipResult,
        EquipResult.parse, .{ self.allocator },
        .{ .method = .POST, .path = path, .payload = payload }
    );
    try self.addOrUpdateCharacter(result.character);

    return result;
}

pub fn getBankGold(self: *Server) APIError!u64 {
    const result = try self.fetch(.{ .method = .GET, .path = "/my/bank/gold" });
    defer result.deinit();

    if (result.status != .ok) {
        return APIError.RequestFailed;
    }
    if (result.body == null) {
        return APIError.ParseFailed;
    }

    const data = json_utils.asObject(result.body.?) orelse return APIError.RequestFailed;
    const quantity = json_utils.getInteger(data, "quantity") orelse return APIError.ParseFailed;
    if (quantity < 0) return APIError.ParseFailed;

    return @intCast(quantity);
}

pub fn getBankItems(self: *Server, allocator: Allocator) APIError!std.ArrayList(ItemIdQuantity) {
    return self.fetchArray(
        allocator,
        APIError,
        null,
        ItemIdQuantity,
        ItemIdQuantity.parse, .{},
        .{ .method = .GET, .path = "/my/bank/items", .paginated = true }
    );
}

pub fn getBankItemQuantity(self: *Server, code: []const u8) APIError!?u64 {
    const query = try std.fmt.allocPrint(self.allocator, "item_code={s}", .{code});
    defer self.allocator.free(query);

    const maybe_items = try self.fetchOptionalArray(
        self.allocator,
        APIError,
        null,
        ItemIdQuantity,
        ItemIdQuantity.parse, .{},
        .{ .method = .GET, .path = "/my/bank/items", .query = query, .paginated = true }
    );
    if (maybe_items == null) {
        return null;
    }

    const items = maybe_items.?;
    defer items.deinit();

    const list_items = items.list.items;
    assert(list_items.len == 1);
    assert(list_items[0].id == try self.getItemId(code));

    return list_items[0].quantity;
}

pub fn getMap(self: *Server, x: i64, y: i64) APIError!?MapTile {
    const position = Position.init(x, y);

    if (self.findMap(position)) |map| {
        return map;
    }

    if (self.prefetched_maps) {
        return null;
    }

    const path = try std.fmt.allocPrint(self.allocator, "/maps/{}/{}", .{x, y});
    defer self.allocator.free(path);

    const result = self.fetchOptionalObject(
        APIError,
        null,
        MapTile,
        MapTile.parse, .{ self.allocator },
        .{ .method = .GET, .path = path }
    );

    if (result) |map| {
        self.addOrUpdateMap(map);
    }

    return result;
}

pub const MapOptions = struct {
    code: ?[]const u8 = null,
    type: ?MapContentType = null,
};

pub fn getMaps(self: *Server, opts: MapOptions) APIError!std.ArrayList(MapTile) {
    if (self.prefetched_maps) {
        var found = std.ArrayList(MapTile).init(self.allocator);
        var mapIter = self.maps.valueIterator();
        while (mapIter.next()) |map| {
            if (opts.type) |content_type| {
                if (map.content == null) continue;
                if (map.content.?.type != content_type) continue;
            }
            if (opts.code) |content_code| {
                if (map.content == null) continue;
                if (!std.mem.eql(u8, map.content.?.code, content_code)) continue;
            }

            try found.append(map.*);
        }
        return found;
    }

    var query = std.ArrayList(u8).init(self.allocator);
    defer query.deinit();

    if (opts.code) |code| {
        try appendQueryParam(&query, "content_code", code);
    }
    if (opts.type) |map_type| {
        try appendQueryParam(&query, "content_type", MapContentTypeUtils.toString(map_type));
    }

    const result = try self.fetchArray(
        self.allocator,
        APIError,
        null,
        MapTile,
        MapTile.parse, .{ self.allocator },
        .{ .method = .GET, .path = "/maps", .paginated = true, .page_size = 100, .query = query.items }
    );

    for (result.items) |map| {
        try self.addOrUpdateMap(map);
    }

    return result;
}

pub fn getItem(self: *Server, code: []const u8) APIError!?Item {
    if (self.items.get(code)) |item| {
        return item;
    }

    if (self.prefetched_items) {
        return null;
    }

    const path = try std.fmt.allocPrint(self.allocator, "/items/{s}", .{code});
    defer self.allocator.free(path);

    const result = try self.fetchOptionalObject(
        APIError,
        null,
        ItemWithGE,
        ItemWithGE.parse, .{ self.allocator },
        .{ .method = .GET, .path = path }
    );

    if (result) |item_with_ge| {
        try self.addOrUpdateItem(item_with_ge.item);

        return item_with_ge.item;
    } else {
        return null;
    }
}

pub fn getItemById(self: *Server, id: ItemId) APIError!?Item {
    const code = self.getItemCode(id) orelse return null;
    return self.getItem(code);
}

pub const ItemOptions = struct {
    craft_material: ?[]const u8 = null,
    craft_skill: ?Skill = null,
    min_level: ?u64 = null,
    max_level: ?u64 = null,
    name: ?[]const u8 = null,
    type: ?ItemType = null,
};

pub fn getItems(self: *Server, opts: ItemOptions) APIError!std.ArrayList(Item) {
    if (self.prefetched_items) {
        var found = std.ArrayList(Item).init(self.allocator);
        var itemIter = self.items.valueIterator();
        while (itemIter.next()) |item| {
            if (opts.craft_skill) |craft_skill| {
                if (item.craft == null) continue;
                if (item.craft.?.skill != craft_skill) continue;
            }
            if (opts.craft_material) |craft_material| {
                if (item.craft == null) continue;
                const recipe = item.craft.?;

                const craft_material_id = try self.getItemId(craft_material);
                const material_quantity = recipe.items.getQuantity(craft_material_id);
                if (material_quantity == 0) continue;
            }
            if (opts.min_level) |min_level| {
                if (item.level < min_level) continue;
            }
            if (opts.max_level) |max_level| {
                if (item.level > max_level) continue;
            }
            if (opts.type) |item_type| {
                if (item.type != item_type) continue;
            }
            if (opts.name) |name| {
                if (std.mem.indexOf(u8, item.name, name) == null) continue;
            }

            try found.append(item.*);
        }
        return found;
    }

    var str_arena = std.heap.ArenaAllocator.init(self.allocator);
    defer str_arena.deinit();

    var query = std.ArrayList(u8).init(self.allocator);
    defer query.deinit();

    if (opts.craft_material) |craft_material| {
        try appendQueryParam(&query, "craft_material", craft_material);
    }
    if (opts.min_level) |min_level| {
        const min_level_str = try std.fmt.allocPrint(str_arena.allocator(), "{}", .{ min_level });
        try appendQueryParam(&query, "min_level", min_level_str);
    }
    if (opts.max_level) |max_level| {
        const max_level_str = try std.fmt.allocPrint(str_arena.allocator(), "{}", .{ max_level });
        try appendQueryParam(&query, "max_level", max_level_str);
    }
    if (opts.name) |name| {
        try appendQueryParam(&query, "name", name);
    }
    if (opts.type) |item_type| {
        try appendQueryParam(&query, "type", ItemTypeUtils.toString(item_type));
    }

    const result = try self.fetchArray(
        self.allocator,
        APIError,
        null,
        Item,
        Item.parse, .{ self.allocator },
        .{ .method = .GET, .path = "/items", .paginated = true, .page_size = 100, .query = query.items }
    );
    errdefer result.deinit();

    for (result.items) |item| {
        try self.addOrUpdateItem(item);
    }

    return result;
}

pub fn getResource(self: *Server, code: []const u8) APIError!?Resource {
    if (self.resources.get(code)) |resource| {
        return resource;
    }

    if (self.prefetched_resources) {
        return null;
    }

    const path = try std.fmt.allocPrint(self.allocator, "/resources/{s}", .{code});
    defer self.allocator.free(path);

    const result = try self.fetchOptionalObject(
        APIError,
        null,
        Resource,
        Resource.parse, .{ self.allocator },
        .{ .method = .GET, .path = path }
    );

    if (result) |resource| {
        try self.addOrUpdateResource(resource);
    }

    return result;
}

pub const ResourceOptions = struct {
    drop: ?[]const u8 = null,
    max_level: ?u64 = null,
    min_level: ?u64 = null,
    skill: ?ResourceSkill = null,
};

pub fn getResources(self: *Server, opts: ResourceOptions) APIError!std.ArrayList(Resource) {
    if (self.prefetched_resources) {
        var found = std.ArrayList(Resource).init(self.allocator);
        var resourceIter = self.resources.valueIterator();
        while (resourceIter.next()) |resource| {
            if (opts.min_level) |min_level| {
                if (resource.level < min_level) continue;
            }
            if (opts.max_level) |max_level| {
                if (resource.level > max_level) continue;
            }
            if (opts.drop) |drop| {
                const item_id = try self.getItemId(drop);
                if (!DropRate.doesListContain(&resource.drops, item_id)) {
                    continue;
                }
            }

            try found.append(resource.*);
        }
        return found;
    }

    var str_arena = std.heap.ArenaAllocator.init(self.allocator);
    defer str_arena.deinit();

    var query = std.ArrayList(u8).init(self.allocator);
    defer query.deinit();

    if (opts.drop) |drop| {
        try appendQueryParam(&query, "drop", drop);
    }
    if (opts.min_level) |min_level| {
        const min_level_str = try std.fmt.allocPrint(str_arena.allocator(), "{}", .{ min_level });
        try appendQueryParam(&query, "min_level", min_level_str);
    }
    if (opts.max_level) |max_level| {
        const max_level_str = try std.fmt.allocPrint(str_arena.allocator(), "{}", .{ max_level });
        try appendQueryParam(&query, "max_level", max_level_str);
    }
    if (opts.skill) |skill| {
        try appendQueryParam(&query, "skill", ResourceSkillUtils.toString(skill));
    }

    const result = try self.fetchArray(
        self.allocator,
        APIError,
        null,
        Resource,
        Resource.parse, .{ self.allocator },
        .{ .method = .GET, .path = "/resources", .paginated = true, .query = query.items }
    );
    errdefer result.deinit();

    for (result.items) |resource| {
        try self.addOrUpdateResource(resource);
    }

    return result;
}

pub fn getMonster(self: *Server, code: []const u8) APIError!?Monster {
    if (self.monsters.get(code)) |monster| {
        return monster;
    }

    if (self.prefetched_monsters) {
        return null;
    }

    const path = try std.fmt.allocPrint(self.allocator, "/monsters/{s}", .{code});
    defer self.allocator.free(path);

    const result = try self.fetchOptionalObject(
        APIError,
        null,
        Monster,
        Monster.parse, .{ self.allocator },
        .{ .method = .GET, .path = path }
    );

    if (result) |monster| {
        try self.addOrUpdateMonster(monster);
    }

    return result;
}

pub const MonsterOptions = struct {
    drop: ?[]const u8 = null,
    max_level: ?u64 = null,
    min_level: ?u64 = null,
};

pub fn getMonsters(self: *Server, opts: MonsterOptions) APIError!std.ArrayList(Monster) {
    if (self.prefetched_monsters) {
        var found = std.ArrayList(Monster).init(self.allocator);
        var monsterIter = self.monsters.valueIterator();
        while (monsterIter.next()) |monster| {
            if (opts.min_level) |min_level| {
                if (monster.level < min_level) continue;
            }
            if (opts.max_level) |max_level| {
                if (monster.level > max_level) continue;
            }
            if (opts.drop) |drop| {
                const item_id = try self.getItemId(drop);
                if (!DropRate.doesListContain(&monster.drops, item_id)) {
                    continue;
                }
            }

            try found.append(monster.*);
        }
        return found;
    }

    var str_arena = std.heap.ArenaAllocator.init(self.allocator);
    defer str_arena.deinit();

    var query = std.ArrayList(u8).init(self.allocator);
    defer query.deinit();

    if (opts.drop) |drop| {
        try appendQueryParam(&query, "drop", drop);
    }
    if (opts.min_level) |min_level| {
        const min_level_str = try std.fmt.allocPrint(str_arena.allocator(), "{}", .{ min_level });
        try appendQueryParam(&query, "min_level", min_level_str);
    }
    if (opts.max_level) |max_level| {
        const max_level_str = try std.fmt.allocPrint(str_arena.allocator(), "{}", .{ max_level });
        try appendQueryParam(&query, "max_level", max_level_str);
    }

    const result = try self.fetchArray(
        self.allocator,
        APIError,
        null,
        Monster,
        Monster.parse, .{ self.allocator },
        .{ .method = .GET, .path = "/monsters", .paginated = true, .query = query.items }
    );

    for (result.items) |monster| {
        try self.addOrUpdateMonster(monster);
    }

    return result;
}